Which JLM Preamp Kit Is For Me?

[ciscan.81]

Hi DIYers

Having read the majority of the massive JLM Baby Animal thread and loads of others on JLM pre's I understand that some of what I am asking has been, in part, covered elsewhere but I thought a fresh take might help other newcomers. It seems the BA thread has been quiet for a while but if tacking onto the end of this is a better place for my post please let me know.

I have been spending a lot of time researching JLM pres lately as I am hoping to up my studio’s ante and make my first preamp purchase.

I have only a little electronics experience having built a beautiful pair of 3 way tower listening speakers, in-line pads, in-line Z patches and the odd lead.

I have been looking at 4 build options:

1.  The two channel Dual 99v Rack kit with the JLM14 input trans and the JLM111 out.

2. The 2 channel 1290 Rack kit

3. Building 2 of each - Dual 99V on a BAD PCB and 1290 macro kit and housing them in one unit on a shared power supply (to save a little money)

4. A BA2 or BA4 Kit using the 99v opamps with transformer setups similar to the pres above. (ie one with a JLM14 and the other with an OEP262A3C on the inputs and JLM111's on the outs) (also toying with the idea of one matched stereo pair and 2 other BA opamp/trans combos to give me 3 different flavours - thats the problem with BA's too many options!!!)

I want to have DI, variable Z and the small round VU meters from JLM (on a buffer) on each channel. (got to have all the options!)

Initially I intend to use the pres mostly for: DI bass, Guitar Cabs, snare, kick and maybe overheads. Something that covers vocals, acoustic guitar, uke, harmonica and percussion is a bonus but not my main focus at this stage. I understand that I'll need quite a few pres to cover all of these instruments in a variety of situations, but that'll come later.

Although I'd love to NOT trot out the usual clichés, I don't know how else to put this so: Sonically I am looking for something vintage, big, fat, warm and punchy (as I'm sure everyone is; never heard of anyone chasing a small, thin, cold-wet-sock sound). Given I want this pre to cover mostly DI bass, guitar and drums a bit of colour is not a bad thing.

The only pre I have used before is a friends Golden Age pre 73 on DI Bass; I liked the sound, but felt it sounded a bit cheap and could be easily bettered. Also, I didn't like the way it broke up when driven hard. I understand Joe's 1290 Macro kit is also a loose take on the N*EVE 1073 but is head and shoulders above the Golden Age...Any thoughts on whether the JLM dual 99v is better again for this application?

My humble mic collection (kind of a starters kit in need of upgrading) currently consists of a Rode NT1A, 2x NT5, Audix i5, Sm57’s and a sennheiser e620. My interface is a Digi002r.

So that's where I'm at.

To aid me with my decision on which pre kit to purchase could anyone with the time and inclination to help out a beginner please advise on the following queries:

1.      Given my brief and vague description of what I am after sonically, which of the Dual99v or 1290 (or 4 x single stage BA variants described above) would you recommend as a first preamp purchase?

2.      Is it possible to put some sort of output trim pot/fader (as on the 1290 and Dual99v) on a BA?

3.      What advantages (both sonically and features wise) do the dual stage pres have over their single stage BA build counterparts?

4.  Is it possible to run 2 of each Dual 99V on a BAD PCB and 1290 macro kits (with TREX2) with all features on a single 48v 40w 840mA
SMPS? If not, which JLM supply should I use in this instance?

5. Does the 1290 macro kit come with or is it possible to add variable input Z?

Many thanks for your time and assistance to help me begin my DIY Preamp journey . I can’t wait to get started!

 

[wolfgang]

Hello!

At first i want to say the JLM-Kits are a very good start for building units. Very well documentet and very very good support from Joe Malone! My first preamps were JLM BA´s. Now i have 12channels of BA´s!

For your Main Recording needs BA´s have enough gain. When you plan to record acoustic instruments and some quiet things you may want to go to the dual BA or the 1290 as they have a lot more gain. especialy the 1290 which has 80dB.

Sound description is difficult but i would say a neve has more bottom end and smooth in the highs where an api-like preamp is "more midrangy" but also faster than a neve. Very different flavour! 

Having 2 Channels of 1290 and 2 Channels API-like is IMHO a good way to start!!!

Regards,
Wolfgang

 

[mulletchuck]

have you thought about the Classic API VP2x kits?  they're super easy to build, and just toss them into an API lunchbox!  max 4-hours per module.  they sound amazing, too!~

 

[Dr_J]

Hi,

I really love JLM!!! No doubt!  
Well, JLM was although my first step into DIY audio!
So, what ever you're gonna to choose, you're gonna be a winner!!!

And DIY is although about to make your own decisions

ROCK-ON!

P.S.: And sometimes is a long, hard way to rock-n-roll
(means keepin' things working!!!)

 

[ciscan.81]

Thanks for all the comments...

At this stage I am honing in on the following:

2 x JLM BA 99v Opamp with JLM14 input and JLM111 output (both with variable Z and 1 channel with DI)
1 x JLM1290 Macro kit with DI
1 x 312 styled BA with either Classic API or Cinemag in and out trans, some kind of 2520 Opamp, DI, variable Z and an output attenuator.

I was hoping to get all this into a 1U case but I think I may be pushing it for front panel space, particularly on my first build.  So I'm thinking 2 separate 1U cases one with the two 99v BA's in one (I'll mount them to one side to leave room for two more channels in the future) and the 1290 and 312 in another case. Will cost a little more for the extra PSU and case but I think it will be worth it for ease of install and also a bit of future-proofing allowing for two more channels down the track (this will happen for sure!)

I have had a look at Classic API; great site.  I am considering getting my API style transformers from there (EA2622 input and EA2503 output) to build a BA 312 style pre, the other alternative is the cinemag CMMI-8PCA or CM-75101APC for inputs and the CMOQ-2S for an output. I am considering either one of Scott Leibers SL-2520, JLM's JLM25HV or The DiY Pill (Fabios) LBG2520 discreet opamps. I figure any one of these combo's is going to give me something awesome! Just have to settle on an option, just waiting on some pricing and availability info to help me decide.

I don't wish to go the classic API VP kit route at this stage because I don't own or plan to own a lunchbox just yet. I am purchasing a couple of other pre kits from JLM and so combining them in one or two cases with shared PSU is a more economical option at this point.

The only thing that is still confusing me a bit is the application of an output attenuator on a BA. I understand that the idea is to allow the preamp to be overdriven and then trim back the output level with some kind of pot after the output trans to prevent clipping the interface input...I'm getting lots of different ideas on the best way to make it happen, anything from a 500ohm to a 25K pot either single or dual ganged or a T-pad like this expensive one from Classic API http://classicapi.com/catalog/product_info.php?cPath=48&products_id=254...any thoughts or experience on wiring attenuators on a BA would be useful. (there doesn't seem to be a lot definitive info on this out there, believe me I have read far and wide!)

I hope to order all my kits and parts this coming week.

I'll post once I get started.

Thanks again!